I always thought rule-based was synonymous with logic-based AI. Logic has axioms and rules of inference, whereas rule-based AI has a knowledge base (essentially, axioms) and if-then rules to create new knowledge (essentially inference rules).
But in their famous article What is a Knowledge Representation?, Davis, Shrobe and Szolovits seem to imply that they are not:
Logic, rules, frames, and so on, embody a viewpoint on the kinds of things that are important in the world. Logic, for example, involves a (fairly minimal) commitment to viewing the world in terms of individual entities and relations between them. Rule-based systems view the world in terms of attribute-object-value triples and the rules of plausible inference that connect them, while frames have us thinking in terms of prototypical objects.
Is this only saying that rule-based are propositional, whereas logic-based is usually meant to mean predicate logic? Or is there more to it than this?